Regular arrangement of collecting venules (RAC) as an endoscopic marker
for exclusion of Helicobacter pylori (H. pylori) infection: A systematic
review and meta-analysis
Background: Helicobacter pylori (H. pylori) is the most common cause of
gastric cancer. Growing evidence suggests that the regular arrangement
of collecting venules (RAC) can be used as an endoscopic marker to
diagnose H. pylori infection. However, data on the diagnostic accuracy
of RAC for H. pylori infection are conflicting. We performed a
systematic review and meta-analysis of relevant studies to determine the
diagnostic accuracy and clinical utility of RAC for the diagnosis of H.
pylori infection. Methods: We systematically searched PubMed, Embase,
Web of Science, and the Cochrane Library between inception and Oct 29,
2020, for studies that assessed the diagnostic accuracy of RAC for H.
pylori infection. Results: The literature search yielded 2921
nonduplicated screened titles, of which 58 underwent full-text review.
Fifteen studies, representing a total of 6621 patients, met the
inclusion criteria. The area under the summary receiver operating
characteristic curve was 0.98 (95% CI 0.96 to 0.99). The pooled
estimates for RAC were 0.98 (95% CI 0.95 to 0.99) for sensitivity and
0.75 (95% CI 0.54 to 0.88) for specificity. The pooled positive
likelihood ratio (PLR) and negative likelihood ratio (NLR) were 3.8
(95% CI 1.9 to 7.7) and 0.03 (95% CI 0.02 to 0.07), respectively.
Conclusions: RAC can be used as an endoscopic marker for exclusion of H.
pylori infection. However, it cannot be recommended as a single
indicator for the confirmation of H. pylori infection. The conclusion of
this study should be treated with caution because significant
heterogeneity exists between the evaluated studies.